Modern communication technology utilizes cables, such as fiber optic cables, most often positioned in a conduit or casing which is buried underground. The installation of such an underground cabling network is a tedious and expensive project. First, usually a trench must be dug and then the conduit, typically of two to four inches in diameter and oftentimes extending for miles in length, is positioned in the trench. The communications cable is then installed in the conduit, either by pulling or pushing the same therethrough. The trench is then filled and the communications network is ready to be utilized, being housed in the conduit safe from the environment of water, gnawing animals and the like.
One of the problems with these systems is that a conduit, particularly of a small size, usually only carries one cable which is positioned therein in a random, sinuous path thereby essentially prohibiting another cable from being readily installed in the existing conduit. Thus, if at a later date the communications system needs to be expanded, as by the addition of another cable, the entire installation process needs to be repeated--at a redundant expense. Bigger conduits, such as those of four inches in diameter or larger, often have smaller conduits placed inside of them. But each of these conduits can only house one cable, and in addition, because of the wall thickness of these internal conduits, much space in the larger conduit is wasted.
One solution to the problem, which has been suggested, is to introduce a strip of material, usually formed of a polyethylene plastic, into the existing conduit which effectively pushes the existing cable to one side in the conduit thereby creating a second chamber in the conduit for the unobstructed installation of a second cable. However, while the polyethylene material is somewhat resilient, such a process is at times difficult in that most underground conduits include many bends and turns which even this resilient material has trouble navigating. As a result, a great deal of force must be utilized to move the strip of material past the existing cable, while at the same time taking care that the strip of material does not damage the existing cable.
As a possible solution to this problem, it has been suggested to form the strip of material with a plurality of notches to allow it to be more flexible and to twist as it is navigating the turns in the conduit. While the notched strip of material has been found to make installation easier, its manufacture is more costly and the possibility of damage to the existing cable is still prevalent.
Most fundamentally, there are other drawbacks to the conduit divider systems described above. First, a conduit having such dividers is only divided into two compartments thereby limiting the capacity of the conduit to two cables. While it might be feasible to further divide the already divided conduit by introducing other strips of material, not only would the installation process have to be repeated, but also that process would be more difficult as there would be less operating space to negotiate turns. Second, and importantly, these divider strips themselves take up valuable and potentially useable space in the conduit, space which could, with an effective divider system, be utilized for additional cables.